Bump @types/leaflet from 1.5.1 to 1.5.2 in /js

Bumps [@types/leaflet](https://github.com/DefinitelyTyped/DefinitelyTyped/tree/HEAD/types/leaflet) from 1.5.1 to 1.5.2.
- [Release notes](https://github.com/DefinitelyTyped/DefinitelyTyped/releases)
- [Commits](https://github.com/DefinitelyTyped/DefinitelyTyped/commits/HEAD/types/leaflet)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

js/package.json

@@ -40,7 +40,7 @@
   },
   "devDependencies": {
     "@types/chai": "^4.2.3",
-    "@types/leaflet": "^1.4.4",
+    "@types/leaflet": "^1.5.2",
     "@types/lodash": "^4.14.123",
     "@types/mocha": "^5.2.6",
     "@vue/cli-plugin-babel": "^3.6.0",